require mutablerecords version that supports pickling
require mutablerecords version that supports pickling

jettisonjoe/openhtf,grybmadsci/openhtf,amyxchen/openhtf,google/openhtf,jettisonjoe/openhtf,google/openhtf,google/openhtf,ShaperTools/openhtf,amyxchen/openhtf,fahhem/openhtf,google/openhtf,fahhem/openhtf,grybmadsci/openhtf,grybmadsci/openhtf,ShaperTools/openhtf,ShaperTools/openhtf,ShaperTools/openhtf,grybmadsci/openhtf,jettisonjoe/openhtf,ShaperTools/openhtf,fahhem/openhtf,fahhem/openhtf,jettisonjoe/openhtf